[Patch net-next v2] net: dump more useful information in netdev_rx_csum_fault()

[Cong Wang <xiyou.wangcong@gmail.com>]

Currently netdev_rx_csum_fault() only shows a device name,
we need more information about the skb for debugging csum
failures.

Sample output:

 ens3: hw csum failure
 dev features: 0x0000000000014b89
 skb len=84 data_len=0 pkt_type=0 gso_size=0 gso_type=0 nr_frags=0 ip_summed=0 csum=0 csum_complete_sw=0 csum_valid=0 csum_level=0

Note, I use pr_err() just to be consistent with the existing one.

Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
---
 include/linux/netdevice.h |  5 +++--
 net/core/datagram.c       |  2 +-
 net/core/dev.c            | 11 +++++++++--
 net/core/skbuff.c         |  4 ++--
 net/sunrpc/socklib.c      |  2 +-
 5 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 487fa5e0e165..5a97ffbff932 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -4342,9 +4342,10 @@ static inline bool can_checksum_protocol(netdev_features_t features,
 }
 
 #ifdef CONFIG_BUG
-void netdev_rx_csum_fault(struct net_device *dev);
+void netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb);
 #else
-static inline void netdev_rx_csum_fault(struct net_device *dev)
+static inline void netdev_rx_csum_fault(struct net_device *dev,
+					struct sk_buff *skb)
 {
 }
 #endif
diff --git a/net/core/datagram.c b/net/core/datagram.c
index 07983b90d2bd..4bf62b1afa3b 100644
--- a/net/core/datagram.c
+++ b/net/core/datagram.c
@@ -767,7 +767,7 @@ int skb_copy_and_csum_datagram_msg(struct sk_buff *skb,
 
 		if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE) &&
 		    !skb->csum_complete_sw)
-			netdev_rx_csum_fault(NULL);
+			netdev_rx_csum_fault(NULL, skb);
 	}
 	return 0;
 fault:
diff --git a/net/core/dev.c b/net/core/dev.c
index bf7e0a471186..5927f6a7c301 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3091,10 +3091,17 @@ EXPORT_SYMBOL(__skb_gso_segment);
 
 /* Take action when hardware reception checksum errors are detected. */
 #ifdef CONFIG_BUG
-void netdev_rx_csum_fault(struct net_device *dev)
+void netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb)
 {
 	if (net_ratelimit()) {
 		pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
+		if (dev)
+			pr_err("dev features: %pNF\n", &dev->features);
+		pr_err("skb len=%u data_len=%u pkt_type=%u gso_size=%u gso_type=%u nr_frags=%u ip_summed=%u csum=%x csum_complete_sw=%d csum_valid=%d csum_level=%u\n",
+		       skb->len, skb->data_len, skb->pkt_type,
+		       skb_shinfo(skb)->gso_size, skb_shinfo(skb)->gso_type,
+		       skb_shinfo(skb)->nr_frags, skb->ip_summed, skb->csum,
+		       skb->csum_complete_sw, skb->csum_valid, skb->csum_level);
 		dump_stack();
 	}
 }
@@ -5781,7 +5788,7 @@ __sum16 __skb_gro_checksum_complete(struct sk_buff *skb)
 	if (likely(!sum)) {
 		if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE) &&
 		    !skb->csum_complete_sw)
-			netdev_rx_csum_fault(skb->dev);
+			netdev_rx_csum_fault(skb->dev, skb);
 	}
 
 	NAPI_GRO_CB(skb)->csum = wsum;
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 396fcb3baad0..fcb1155a00ec 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -2653,7 +2653,7 @@ __sum16 __skb_checksum_complete_head(struct sk_buff *skb, int len)
 	if (likely(!sum)) {
 		if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE) &&
 		    !skb->csum_complete_sw)
-			netdev_rx_csum_fault(skb->dev);
+			netdev_rx_csum_fault(skb->dev, skb);
 	}
 	if (!skb_shared(skb))
 		skb->csum_valid = !sum;
@@ -2673,7 +2673,7 @@ __sum16 __skb_checksum_complete(struct sk_buff *skb)
 	if (likely(!sum)) {
 		if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE) &&
 		    !skb->csum_complete_sw)
-			netdev_rx_csum_fault(skb->dev);
+			netdev_rx_csum_fault(skb->dev, skb);
 	}
 
 	if (!skb_shared(skb)) {
diff --git a/net/sunrpc/socklib.c b/net/sunrpc/socklib.c
index 9062967575c4..7e55cfc69697 100644
--- a/net/sunrpc/socklib.c
+++ b/net/sunrpc/socklib.c
@@ -175,7 +175,7 @@ int csum_partial_copy_to_xdr(struct xdr_buf *xdr, struct sk_buff *skb)
 		return -1;
 	if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE) &&
 	    !skb->csum_complete_sw)
-		netdev_rx_csum_fault(skb->dev);
+		netdev_rx_csum_fault(skb->dev, skb);
 	return 0;
 no_checksum:
 	if (xdr_partial_copy_from_skb(xdr, 0, &desc, xdr_skb_read_bits) < 0)
-- 
2.19.1